I'm a big fan of negative
social preferencing as a way to penalize
force initiators—especially, but not exclusively, bad actors who
perceive themselves as enjoying a high degree of immunity/impunity
because they work for the world's larger and more powerful criminal
gangs, aka "governments."

When it comes to negative social preferencing, the more the
merrier: It should be crowd-sourced. If I refuse to have anything to
do with you, no biggie. But if you can't get a sandwich at your
favorite deli, receive communion at your church of choice, etc.
because everyone thinks you're an asshole and doesn't want to have
anything to do with you, you've got a real incentive to stop
initiating force against others, apologize for initiating force
against others, and make restitution to those you've harmed.

And of course a pre-condition of effectivenegative social
preferencing is "doxing"—amassing/aggregating publicly
available information on evildoers such that their social weak spots
are identifiable. If our target lives in Tacoma, Washington and
doesn't travel much, being banned from a nightclub in Santa Fe, New
Mexico probably won't make a big difference to hir quality of life;
if, on the other hand, our target is an observant Muslim and suddenly
can't find any place to sell hir halal food, that smarts. In addition
to shunning bad people, it's important to help identify those bad
people and their weak spots.